Door or panel latch assembly

ABSTRACT

A rotary operated latch assembly having a latch member mounted on a threaded shaft for axial movement along the shaft and pivotal movement about the shaft, the latch assembly being mounted onto a panel member whereby rotation of the threaded shaft results in the latch member moving toward or away from the panel member engaging or disengaging with a door or panel frame during said movement.

United States Patent [191 Hammann Nov. 27, 1973 DOOR 0R PANEL LATCH ASSEMBLY [75] Inventor: Paul E. Hammann, Bettendorf, Iowa [73] Assignee: American Air Filter Company, Inc.,

Louisville, Ky.

[22] Filed: Sept. 30, 1971 [21] Appl. No.: 185,297

[52] US. Cl. 292/64, 292/256.73 [51] Int. Cl. E05c 9/00 [58] Field of Search 292/256.73, 256.75,

[56] References Cited UNITED STATES PATENTS 10/1931 Olley et a1. 292/256.73 1/1968 Soltis 292/256.73

FOREIGN PATENTS OR APPLICATIONS Great Britain 292/212 12/1940 France; 292/64 7/1897 Great Britain 292/251 Primary Examiner-Richard E. Moore Attorney-Charles G. Lamb et a1.

57' ABSTRACT A rotary operated latch assembly having a latch member mounted on a threaded shaft for axial movement along the shaft and pivotal movement about the shaft, the latch assembly being mounted onto a panel member whereby rotation of the threaded shaft results in the latch member moving toward or away from the panel member engaging or disengaging with a door or panel frame during said movement,

7 Claims, 3 Drawing Figures DOOR OR PANEL LATCH ASSEMBLY BACKGROUND OF 'THE INVENTION The present invention relates to a door latch assembly of the type which is adaptable for mounting along the edges of a door or panel member which overlaps a wall or frame wherein the latching member is swingable over the inside frame of the door or panel opening to lock the panel against the frame. The present invention is particularly concerned with a latch assembly having a latch member mounted on a threaded shaft for axial movement along the shaft and pivotal movement about the shaft, the latch member being provided with stop means to cooperate with pivotal movement of the latch member for engaging and disengaging relationships with a coextensive panel member, such as a door frame.

Door latch assemblies adaptable for mounting along the edges of a door member which overlap walls or frames are well known in the art. Several of these assemblies are designed for the latching member to be swingable over the inside wall or frame. However, these assemblies have been found complex in construction and erection, requiring elaborate installation arrangements on door or panel members.

SUMMARY OF THE INVENTION In the present invention, it is recognized that it is desirable to provide a panel or door latch assembly for latching overlapping coextensive panels, the latch assembly being mounted along the edges of one of the panels. It is further recognized that it is desirable to provide a latch assembly for use with a panel that fits outside a panel frame, the assembly having a latch member swingable over the inside of the frame. Also, it is recognized that it is desirable to have door latch assemblies which are economical and easily constructed for use in fluid treating equipment, particularly air filtration equipment.

The present invention advantageously provides a straightforward arrangement of a door latch assembly to be used in association with a door or panel closure member to give a fluid tight seal between the edge of a door or panel member and a door or panel frame in a housing.

Various other features of the present invention will become obvious to those skilled in the art upon reading the disclosure set forth hereinafter.

More particularly, the present invention provides a latch assembly for latching the overlapping edges of first and second coextensive panels comprising a bracket having a base portion and two leg portions, the bracket being fixedly attached to the first panel; a threaded shaft adapted to project in a freely rotatable manner through aligned apertures in the first panel and at least one of the legs of the bracket; a latch member having an internally threaded aperture therein adaptable for mounting onto the threaded shaft for axial movement along the shaft member and pivotal movement about the axis of the shaft'member, the latch member being adaptable for engaging relationship with the second panel, the second panel having edges coextensive with the edges of the first panel; and resilient means communicating with the latch and adaptable for exerting sufficient tension on the latch to provide pivotal movement of the latch in the direction of rotation of the shaft.

It is to be understood that the description of the examples of the present invention given hereinafter are not by way of limitation and that various modifications within the scope of the present invention will occur to those'skilled in the art upon reading the disclosures set forth hereinafter. Referring now to the figures:

FIG. 1 is a perspective view ilustrating the closure of an opening in an air handling unit using a plurality of door latch assemblies of the present invention;

FIG. 2 is an enlarged cross-sectional view of a door latch assembly taken along the plane through 2-2 of FIG. 1; and

FIG. 3 is an enlarged exploded perspective illustration of a door latch assembly of the present invention. In FIG. 1, a panel member 1 is provided for covering an opening in wall 2 of an air cleaning equipment housing 10 utilizing a plurality of door latch assemblies 3. The door latch assemblies 3, hereinafter described, are provided at selected locations along the edges of panel member 1 for latching panel member 1 to the coextensive panel member or panel frame 5 of wall 2.

Referring now to FIGS. 2 and 3 there is illustrated one door latch assembly 3 mounted on a panel member 1 to permit the latch to engage with a panel frame 5. Latch assembly 3 is attached to panel member 1 by means of fasteners, such as rivets 4. The latch assembly 3 includes a U-shaped bracket 7, screw 6, a coil spring 8, a latch member 9, a nut 11, and a pin 12.

U-shaped bracket 7 is provided with a pair of spaced apertures 18 in leg 24 for receiving fasteners 4 for attaching the bracket 7 to the panel member 1. Bracket 7 is further provided with unthreaded intermediate aperture 13 in leg 24 and unthreaded aperture 14 in opposed leg 26, the apertures 13 and 14 being in axial alignment for receiving screw 6 therethrough, screw 6 being freely rotatable in apertures 13 and 14.

Screw 6 has an enlarged non-threaded center parted head 22 of a diameter sufficient to prevent movement of head 22 through an axially aligned aperture (not shown) in panel memberl. Screw 6 is further provided with a threaded shaft portion 21 of a diameter adaptable for passing through the aperture (not shown) in panel member 1 and aligned apertures 13 and 14.

Latch member 9, a polyhedron having opposed spaced parallel surfaces of trapezoidal configuration, is provided with an internally threaded aperture 16, a first contact surface 29, and a second surface 30 including a contact edge 31. Aperture 16 is adapted to receive shaft 21 in threaded engagement therewith for axial movement of latch member 9 thereon. The second surface 30 including contact edge 311, contact surface 31 being the transversely extending edge connecting the apexes of the trapezoidal surfaces, is adapted to move angularly toward the base 28 upon axial movement of latch member 9 toward frame 5, latch member 9 being adaptable for pivotal movement with one face thereof engaging with extremity of right angle lip 27 of frame 5. The first contact surface 29, contact surface 29 being one of the surfaces opposite the contact edge 31 is adapted to move angularly toward the base 28 upon axial movement of latch member 9 along shaft 21 away from panel frame 5. Furthermore, trapezoidal configured latch member 9 is sized so that when surface 29 is in contact with base 28 the latch member 9 is in nonlatching position, but when edge 31 is in contact with base 28 the latch member 9 is in latching position.

Coil spring 8 through which screw 6 passes is adaptable for positioning between and communicating with leg 24 of U-shaped bracket 7 and the latch member 9. Spring 8 is further adapted for exerting sufficient tension on latch member 9 to provide pivotal movement of latch member 9 in the direction of the rotation of the shaft 21.

Screw engaged with the threaded shaft 21 is a castle or hex nut 1 1. A through aperture 17 is provided at the extremity of threaded shaft 21 transverse of the shaft 21 for receiving pin 12. Pin 12 is of a preselected length greater than the distance through the aperture 17 and is provided to limit axial movement of the nut 11 upon rotation of threaded shaft 21.

In attaching the door latch assembly 3 to the panel member 1, U-shaped bracket 7 is attached to the panel member 1 by fasteners 4, the fasteners 4 being inserted through spaced apertures 18 in the leg 24 of U-shaped bracket 7. Screw 6 is inserted through washer 23, an aperture (not shown) in panel member 1, and aperture 13 in leg 24 of U-shaped bracket 7, the aperture 13 being in axial alignment with the aperture (not shown) in panel member 1 and adapted for receiving screw 6 for freely rotatable movement therein. Coil spring 8, being adapted to be received by the threaded shaft 21 of screw six, is placed onto threaded shaft 21.

Latch member 9, having an aperture 16 therein with internal threads for receiving shaft 21 in threaded engagement therethrough is positioned for receiving the threaded shaft 21 upon rotating shaft 21. In a preferred embodiment, threading of latch member 9 and shaft 21 is preselected for combination with a preselected trapezoidal shape of latch member 9 so that when the shaft 21 is rotated for axial movement of latch member 9 along shaft 21 toward lip 27, latch member 9 moves pivotally in a direction so that edge 31 contacts base 28 and when the shaft 21 is rotated for axial movement of latch member 9 away from lip 27, latch member 9 moves pivotally in a direction so that surface 29 contacts base 28.

The threaded shaft 21 is passed through the aperture 16 a preselected distance past latch member 9. Shaft 21 is passed through non-threaded aperture 14 of the leg 26 of U-shaped bracket 7, aperture 14 being adapted for receiving shaft 21 for freely rotatable movement therein. Nut 11 is screw engaged with the threaded shaft 21 and the nut l 1 is rotated on the threaded shaft 21 until it is properly aligned with aperture 17. Pin 12 is then inserted through aperture 17 to hold the nut 11 on the threaded shaft 21.

In sealing an opening in a wall, screw 6 is rotated with latch member 9 moving axially along shaft 21 until latch member 9 contacts lip 27 and pivotally until the edge 31 is in communication with the base 28 of U- shaped bracket 7. Generaly, a gasket 19 is provided on the outside of wall 2 for fluid tight sealing between panel member 1 and wall 2 when latch member 9 is drawn tight against lip 27 of frame 5.

In the aforementioned example it is illustrated that the means for limiting axial movement of the threaded shaft 21 is the center-parted head 22 of screw 6 at one end and nut 11 in communicative relation with leg 26 at the other. However, it is contemplated that other means may be used for limitation of axial movement of shaft 21.

Thus, it will be realized that various changes may be made to the specific embodiment shown and described without departing from the principal and spirit of the present invention.

I claim:

Claim 1. A latch assembly for latching the overlapping edges of first and second coextensive panels comprising a U-shaped bracket having a base portion and two leg portions, said bracket having one leg fixedly attached to said first panel; a threaded shaft projecting in a freely rotatable manner through aligned apertures in said first panel and said legs of said bracket; a latch member having an internaly threaded aperture therein mounted onto said threaded shaft for axial movement along said shaft and pivotal movement about the axis of said shaft member, said latch member being adaptable for engaging with a second panel, said second panel, said second panel having edges coextensive with the edges of said first panel; and resilient means directly communicating with said latch member and adaptable for exerting sufficient tension on said latch member to provide pivotal movement of said latch member in the direction of rotation of said shaft, said latch member being a polyhedron having opposed spaced parallel surfaces of trapezoidal configuration with a transversely extending contact edge connecting the apexes of said trapezoidal surfaces, said polyhedron further having a contact surface disposed between said trapezoidal surfaces and opposite said contact edge, said contact surface being adjacent one of the surfaces determining said contact edge whereby the contact surface and the adjacent surface are joined by an obtuse angle, said contact edge contracting with the base of said bracket in a first position and said contact surface contacting said base of said bracket in a second position.

2. The latch assembly of claim 1 including means limiting said threaded shaft in its axial movement through said first panel.

3. The latch assembly of claim 2 wherein the means limiting said threaded shaft in its movement through said first panel includes a nut and a pin at the end of said threaded shaft opposite the end extending through said panel, said nut being screw engaged with said threaded shaft, said pin being inserted transversely through said threaded shaft and aligned with said nut preventing axial movement of said nut upon rotational movement of said threaded shaft; and an enlarged nonthreaded head at the end of said threaded shaft extending through said first panel, said head being of a diameter sufficient to prevent movement through said aperture in said first panel.

4. The latch member assembly of claim 1, said latch being of trapezoidal configuration and adapted to be in a non-latching position when said first contact surface is in contact with said base and a latching position when said contact edge of said second surface is in contact with said base.

5. The latch member assembly of claim 1, said latch being adapted for pivotal movement of said second surface including said contact edge toward said base when said shaft is rotated for axial movement of said latch in the direction toward said base when said shaft is rotated for axial movement of said latch in the direction away from said second panel.

6. The latch assembly of claim 1 wherein said resilient means is a coiled spring.

7. The latch assembly of claim 6, said threaded shaft member passing through said coiled spring in freely rotatable relation therein, said coiled spring being disposed between and in communication with one leg of said U-shaped bracket and said latch member. 

1. A latch assembly for latching the overlapping edges of first and second coextensive panels comprising a U-shaped bracket having a base portion and two leg portions, said bracket having one leg fixedly attached to said first panel; a threaded shaft projecting in a freely rotatable manner through aligned apertures in said first panel and said legs of said bracket; a latch member having an internally threaded aperture therein mounted onto said threaded shaft for axial movement along said shaft and pivotal movement about the axis of said shaft member, said latch member being adaptable for engaging with a second panel, said second panel, said second panel having edges coextensive with the edges of said first panel; and resilient means directly communicating with said latch member and adaptable for exerting sufficient tension on said latch member to Provide pivotal movement of said latch member in the direction of rotation of said shaft, said latch member being a polyhedron having opposed spaced parallel surfaces of trapezoidal configuration with a transversely extending contact edge connecting the apexes of said trapezoidal surfaces, said polyhedron further having a contact surface disposed between said trapezoidal surfaces and opposite said contact edge, said contact surface being adjacent one of the surfaces determining said contact edge whereby the contact surface and the adjacent surface are joined by an obtuse angle, said contact edge contracting with the base of said bracket in a first position and said contact surface contacting said base of said bracket in a second position.
 2. The latch assembly of claim 1 including means limiting said threaded shaft in its axial movement through said first panel.
 3. The latch assembly of claim 2 wherein the means limiting said threaded shaft in its movement through said first panel includes a nut and a pin at the end of said threaded shaft opposite the end extending through said panel, said nut being screw engaged with said threaded shaft, said pin being inserted transversely through said threaded shaft and aligned with said nut preventing axial movement of said nut upon rotational movement of said threaded shaft; and an enlarged nonthreaded head at the end of said threaded shaft extending through said first panel, said head being of a diameter sufficient to prevent movement through said aperture in said first panel.
 4. The latch member assembly of claim 1, said latch being of trapezoidal configuration and adapted to be in a non-latching position when said first contact surface is in contact with said base and a latching position when said contact edge of said second surface is in contact with said base.
 5. The latch member assembly of claim 1, said latch being adapted for pivotal movement of said second surface including said contact edge toward said base when said shaft is rotated for axial movement of said latch in the direction toward said base when said shaft is rotated for axial movement of said latch in the direction away from said second panel.
 6. The latch assembly of claim 1 wherein said resilient means is a coiled spring.
 7. The latch assembly of claim 6, said threaded shaft member passing through said coiled spring in freely rotatable relation therein, said coiled spring being disposed between and in communication with one leg of said U-shaped bracket and said latch member. 